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<div class="title">homkermap.c File Reference</div>  </div>
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<p>Homogeneous kernel map - Definition.  
<a href="#details">More...</a></p>
<div class="textblock"><code>#include &quot;<a class="el" href="homkermap_8h.html">homkermap.h</a>&quot;</code><br/>
<code>#include &quot;<a class="el" href="mathop_8h.html">mathop.h</a>&quot;</code><br/>
<code>#include &lt;math.h&gt;</code><br/>
<code>#include &quot;<a class="el" href="homkermap_8c.html">homkermap.c</a>&quot;</code><br/>
</div><table class="memberdecls">
<tr><td colspan="2"><h2><a name="func-members"></a>
Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">double&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="homkermap_8c.html#a86c2873e6353bcfcbaa4abd4314af9d8">vl_homogeneouskernelmap_get_spectrum</a> (<a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> const *self, double omega)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Sample the kernel specturm.  <a href="#a86c2873e6353bcfcbaa4abd4314af9d8"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">double&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="homkermap_8c.html#ac2d0164090862bfa17f25364447676e7">vl_homogeneouskernelmap_get_smooth_spectrum</a> (<a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> const *self, double omega)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Sample the smoothed kernel spectrum.  <a href="#ac2d0164090862bfa17f25364447676e7"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="homkermap_8c.html#a87e86a2981550ae60f565575c32966ea">vl_homogeneouskernelmap_new</a> (<a class="el" href="homkermap_8h.html#a13074dd7edec5d8c86dde5da80e8d8d8">VlHomogeneousKernelType</a> kernelType, double gamma, <a class="el" href="host_8h.html#a0ee26101458c663510d620e3ee7e2555">vl_size</a> order, double period, <a class="el" href="homkermap_8h.html#a35a05da3e1eb781a6fa997ec9be69a62">VlHomogeneousKernelMapWindowType</a> windowType)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Create a new homgeneous kernel map.  <a href="#a87e86a2981550ae60f565575c32966ea"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="homkermap_8c.html#a9a059f792833cb10e62f5f476f99f0da">vl_homogeneouskernelmap_delete</a> (<a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> *self)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Delete a map object.  <a href="#a9a059f792833cb10e62f5f476f99f0da"></a><br/></td></tr>
</table>
<hr/><a name="details" id="details"></a><h2>Detailed Description</h2>
<div class="textblock"><dl class="author"><dt><b>Author:</b></dt><dd>Andrea Vedaldi </dd></dl>
</div><hr/><h2>Function Documentation</h2>
<a class="anchor" id="a9a059f792833cb10e62f5f476f99f0da"></a><!-- doxytag: member="homkermap.c::vl_homogeneouskernelmap_delete" ref="a9a059f792833cb10e62f5f476f99f0da" args="(VlHomogeneousKernelMap *self)" -->
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<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">void vl_homogeneouskernelmap_delete </td>
          <td>(</td>
          <td class="paramtype"><a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> *&#160;</td>
          <td class="paramname"><em>self</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">self</td><td>map object. The function deletes the specified map object. </td></tr>
  </table>
  </dd>
</dl>

</div>
</div>
<a class="anchor" id="ac2d0164090862bfa17f25364447676e7"></a><!-- doxytag: member="homkermap.c::vl_homogeneouskernelmap_get_smooth_spectrum" ref="ac2d0164090862bfa17f25364447676e7" args="(VlHomogeneousKernelMap const *self, double omega)" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">double vl_homogeneouskernelmap_get_smooth_spectrum </td>
          <td>(</td>
          <td class="paramtype"><a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> const *&#160;</td>
          <td class="paramname"><em>self</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>omega</em>&#160;</td>
        </tr>
        <tr>
          <td></td>
          <td>)</td>
          <td></td><td><code> [inline]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">self</td><td>homogeneous kernel map. </td></tr>
    <tr><td class="paramname">omega</td><td>sampling frequency. </td></tr>
  </table>
  </dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>the spectrum sampled at <em>omega</em> after smoothing. </dd></dl>

</div>
</div>
<a class="anchor" id="a86c2873e6353bcfcbaa4abd4314af9d8"></a><!-- doxytag: member="homkermap.c::vl_homogeneouskernelmap_get_spectrum" ref="a86c2873e6353bcfcbaa4abd4314af9d8" args="(VlHomogeneousKernelMap const *self, double omega)" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">double vl_homogeneouskernelmap_get_spectrum </td>
          <td>(</td>
          <td class="paramtype"><a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a> const *&#160;</td>
          <td class="paramname"><em>self</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>omega</em>&#160;</td>
        </tr>
        <tr>
          <td></td>
          <td>)</td>
          <td></td><td><code> [inline]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">self</td><td>homogeneous kernel map. </td></tr>
    <tr><td class="paramname">omega</td><td>sampling frequency. </td></tr>
  </table>
  </dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>the spectrum sampled at <em>omega</em>. </dd></dl>

</div>
</div>
<a class="anchor" id="a87e86a2981550ae60f565575c32966ea"></a><!-- doxytag: member="homkermap.c::vl_homogeneouskernelmap_new" ref="a87e86a2981550ae60f565575c32966ea" args="(VlHomogeneousKernelType kernelType, double gamma, vl_size order, double period, VlHomogeneousKernelMapWindowType windowType)" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname"><a class="el" href="structVlHomogeneousKernelMap.html">VlHomogeneousKernelMap</a>* vl_homogeneouskernelmap_new </td>
          <td>(</td>
          <td class="paramtype"><a class="el" href="homkermap_8h.html#a13074dd7edec5d8c86dde5da80e8d8d8">VlHomogeneousKernelType</a>&#160;</td>
          <td class="paramname"><em>kernelType</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>gamma</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype"><a class="el" href="host_8h.html#a0ee26101458c663510d620e3ee7e2555">vl_size</a>&#160;</td>
          <td class="paramname"><em>order</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>period</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype"><a class="el" href="homkermap_8h.html#a35a05da3e1eb781a6fa997ec9be69a62">VlHomogeneousKernelMapWindowType</a>&#160;</td>
          <td class="paramname"><em>windowType</em>&#160;</td>
        </tr>
        <tr>
          <td></td>
          <td>)</td>
          <td></td><td></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">kernelType</td><td>type of homogeneous kernel. </td></tr>
    <tr><td class="paramname">gamma</td><td>kernel homogeneity degree. </td></tr>
    <tr><td class="paramname">order</td><td>approximation order. </td></tr>
    <tr><td class="paramname">period</td><td>kernel period. </td></tr>
    <tr><td class="paramname">windowType</td><td>type of window used to truncate the kernel. </td></tr>
  </table>
  </dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>the new homogeneous kernel map.</dd></dl>
<p>The function intializes a new homogeneous kernel map for the specified kernel type, homogeneity degree, approximation order, period, and truncation window. See <a class="el" href="homkermap.html#homkermap-overview">Overview</a> for details.</p>
<p>The homogeneity degree <code>gamma</code> must be positive (the standard kernels are obtained by setting <code>gamma</code> to 1). When unsure, set <code>windowType</code> to <a class="el" href="homkermap_8h.html#a35a05da3e1eb781a6fa997ec9be69a62a83070b8b6be773c61bc3f19fc4583053">VlHomogeneousKernelMapWindowRectangular</a>. The <code>period</code> should be non-negative; specifying a negative or null value causes the function to switch to a default value.</p>
<p>The function returns <code>NULL</code> if there is not enough free memory. </p>

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